Shaun Edwards has challenged his "heartbroken" Wales team to qualify for the World Cup quarter-finals "the hard way" after their South Africa defeat.

Wales were beaten 17-16 by the reigning champions in their World Cup opener.

And defence coach Edwards warns Wales cannot afford to lose another Pool D match if they want to progress to the knockout stages in New Zealand.

"This is a setback," said Edwards. "And we'll just have to do it the hard way to be a success at this World Cup."

Wales dominated for much of the game in Wellington and led deep into the second half after Warren Gatland's men scored 13 unanswered points, having trailed 10-3.

The Welsh made the Springboks look second best in an epic encounter but South Africa prevailed when Morne Steyn converted substitute Francois Hougaard's 65th-minute try, denying Wales what would have been just their second ever win over the Boks.

Wales fly-half Rhys Priestland missed a drop-goal from in front of the posts while the Welsh players felt a James Hook penalty attempt should have been given by the officials.

WALES' WORLD CUP FIXTURES

v Samoa: 18 Sept, Hamilton

v Namibia: 26 Sept, New Plymouth

v Fiji: 02 Oct, Hamilton

But Edwards told his "sombre" players that "the situation we find ourselves in is an opportunity to show true character".

He added: "If you look through sports history, all great sportsman have always had setbacks and the sign of a great sportsman is to come back from those setbacks."

Wales face Samoa in Hamilton on Sunday before facing Namibia and Fiji in their final Pool D games.

And Wales centre Jamie Roberts insists his team-mates must not dwell on their "cruel" defeat.

"When you lose by one point to the world champions in your opening game of the World Cup, it's a pretty bitter pill to swallow," said the British and Irish Lions player.

"It's heartbreaking. The changing room was a very sombre place. You can't really put it into words, but to put it simply, it was a game we should have won.

"Territorially, I thought we outplayed them. I will probably lie in bed thinking that was one hell of a game that got away from us. I thought we deserved to win, and we should have won.

"We just need to pick our heads up. It is a week's turnaround until we play Samoa and we need to win our remaining three games."